Concurrent testing of analog filters using a programmable biquad

A practical architecture for implementing switched-capacitor filters that can be concurrently tested is reported. Signals applied during the normal operation of the filter allow for assessing whether or not the filter is under a fault condition. Instead of a full duplication of the filter, this approach only requires an extra filter stage (which must be electrically programmable) and a logic control circuit. Experimental results seem promising and encourage further research upon this topic